This invention relates to a pharmaceutical composition for the treatment of psoriasis vulgaris.
Psoriasis is characterized by pink or red lesions which are covered with silvery scales. These lesions are often found in the folds of the elbows and knees, the scalp and the genitoanal area. The condition is marked by accelerated turnover of the epidermal layer of the skin and consequential epidermal thickness. Psoriasis vulgaris is the common form of the disease.
While normal epidermal turnover occurs every 25-30 days, in psoriatic skin it occurs approximately every 3-4 days. At this rate, the skin color is often affected, resulting in too much or too little pigmentation.
The duration of psoriasis vulgaris is variable. Psoriatic lesions may last a lifetime, or they may disappear within a short period of time.
Many attempts have been made in the past to cure psoriasis vulgaris. The first attempts to treat this condition were through topical agents containing a variety of active ingredients. One of the more popular of these topical agents is an ointment containing salicylic acid as the active ingredient. However, because salicylic acid is an irritant, its use has sometimes resulted in a worsening of the condition.
Another popular active ingredient of the topical agents has been corticosteriods such as hydrocortisone. The corticosteriods have significant suppressive activity which affects psoriasis. However, they also have many untoward effects, such as local atrophy and systemic absorption. There is also a danger of relapse upon discontinuance of use.
In a different approach, exposure to ultraviolet light has been tried, but has met with limited success. Combination therapy of ultraviolet light and coal tar preparations appear to be more effective than the ultraviolet light alone. However, some patients incur a worsening of their condition upon the application of coal tar to affected areas.
More recently, the oral administration of the corticosteriods has shown significant suppressive activity on psoriasis. This course of treatment has considerable drawbacks, including the usual systemic side effects. Moreover, the condition often becomes worse than it was initially upon the cessation of this therapy. For this reason, the systemic use of the corticosteriods is limited to the most severe forms of psoriasis only.
Other systemic treatments which have been tried include cytostatic therapy and Vitamin A and C treatments. The consensus is that these treatments are of questionable value.
All in all, the treatments for psoriasis vulgaris which have been proposed have not been successful. These prior art treatments are either ineffective or accompanied by untoward side effects.
It is therefore an object of the present invention to overcome the deficiencies of the prior art by providing a new composition for the treatment of psoriasis vulgaris in humans and a method for its preparation.
A particular object of the invention is the identification of a mixture which has a unique combination of ingredients which are particularly advantageous in treating the skin areas afflicted with psoriasis vulgaris.
It is a further object of the invention to provide a composition which is effective in the treatment of psoriasis vulgaris and which does not produce harmful side effects.